Fermentation parameters of kikuyu grass (Pennisetum clandestinum) by in vitro gas production technique (IVGPT)

摘要

Methane (CH_4) is a byproduct of ruminal fermentation whose production is directly related to forage quality, which in rum is affected by a myriad of environmental factors. In general the quality of pastures in the tropics range from medium to poor due to a high content of lignocellulosic material of low digestibility and a low content of other components, such as soluble carbohydrates and protein (Correa et al, 2008). CH_4 produced by enteric fermentation from cattle rumen represents a major sourceof greenhouse gases (GHG). By measuring these emissions the impact of dairy production systems on the climate change can be determine.In Colombia and in specifically in the Department of Antioquia, dairy herds are characterized by using diets based on kikuyu grass (Pennisetum clandestinum) supplemented with concentrates. Once in the rumen the forage /concentrate combination are used assubstrate for ruminal fermentation to generate usable energy but also unusable one represented by methane production. The energy losses due to diets based on kikuyu are unknown. Thus, the measurement of its fermentation products has become an importantnecessity in order to achieve greater efficiency in the livestock production systems which are also environmentally friendly and economically competitive. Despite some important progress in Colombia, the potential impact of livestock on global warming isstill unknown so that measuring of CH_4 emissions is a crucial imperative. In the dairy zone located in the northern part of Antioquia, where daily two millions liters of milk are produced, there are around 185,000 ha in kikuyu pasture. The overall objective of this research was to measure the parameters of fermentation and CH_4 production of kikuyu pastures from dairy systems of Antioquia, using the in vitro gas production technique (IVGPT).